If you'd hadn't already secured your pre-order with a local retailer, online was the next best choice. Amazon recently announced that they would be taking pre-orders on its website from 9am Tue 21st of Nov, today.
Although 40 minutes later than scheduled, the online giant opened its virtual doors and a flood of users scrambled desperatly to seal a Wii pre-order. Because of the delay, it was though that 100s of people were sitting at their computers hitting refresh for the entire 40 minutes!
Oh well, Amazon, you've tried your best. If you were one of the unlucky ones, we'd advise to keep trying other sources, Wii is probably going to sell out on launch day.